The most important prognostic variable in determining outcome after ICH is the level of medical support provided. Withdrawal of support in patients felt likely to have a "poor outcome" biases predictive models and leads to self-fulfilling prophecies. Our data show that individual patients in traditionally "poor outcome" categories can have a reasonable neurologic outcome when treated aggressively.
In vitro ischemia models have utilized oxygen, or oxygen and glucose deprivation to simulate ischemic neuronal injury. Combined oxygen and glucose deprivation can induce neuronal damage which is in part mediated through NMDA receptors. Severe oxygen deprivation alone however can cause neuronal injury which is not NMDA mediated. We tested the hypothesis that NMDA, or non-NMDA receptor mediated mechanisms may predominate, to induce neuronal injury following severe oxygen deprivation depending on the presence of glucose. We found that NMDA receptor blockade using dizocilpine (MK-801), DL-2-amino-5- phosphonovaleric acid (APV), or CGS 19755, was highly effective in reducing CA1 injury in organotypic hippocampal cultures, caused by complete oxygen and glucose deprivation. Complete oxygen deprivation alone however, caused CA1 neuronal injury which was not diminished using NMDA receptor blockade alone with MK-801 or APV, or in combination with AMPA/kainate receptor blockade using 6-cyano-7- dinitroquinoxalone-2,3-dione (CNQX). Neuronal protective strategies which act primarily through non-glutamate dependent mechanisms, including hypothermia, low chloride and calcium, and the free radical scavenger, alpha-phenyl-tert-butyl nitrone (PBN), provided neuronal protection against complete oxygen, as well as combined oxygen/glucose deprivation. Raising the pH using Hepes buffer during complete oxygen deprivation did not result in neuronal protection by NMDA receptor blockade. Partial oxygen deprivation alone, partial oxygen deprivation combined with glucose deprivation, glucose deprivation alone, and also glutamate exposure, all produced neuronal damage that was reduced by NMDA receptor blockade. The presence of glucose during complete oxygen deprivation appears to prevent glutamate receptor blockade from reducing neuronal injury in organotypic hippocampal cultures.
To determine how clinical grade after subarachnoid hemorrhage impacts operative characteristics and the incidence of intra- and postoperative surgical complications, we retrospectively compared the surgical management of all good grade (n = 224) and poor grade (n = 131) patients who suffered ruptured anterior circulation aneurysms between 1983 and 1993. The majority of good grade (74.2%) and poor grade (89.8%) patients underwent surgery < 3 days after subarachnoid hemorrhage. The results in this series demonstrate that severe cerebral swelling, often secondary to intracerebral hemorrhage, was significantly more frequent in poor grade patients. The incidence of complications, such as failure to occlude the aneurysm, major vessel occlusion, intraoperative aneurysm rupture, or surgical contusion, however, was similar in poor grade and good grade patients. We conclude, therefore, that except for severe cerebral swelling associated with intracerebral hemorrhage, the risk of surgical complications is similar in good and poor grade patients undergoing surgical repair of ruptured anterior circulation aneurysms.
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